Although it's been more than four years since Timmothy Pitzen was reported missing, the Aurora boy's mysterious disappearance has recently been catapulted into the national spotlight, and police are hoping the exposure leads to new clues in the case.

In September, Pitzen's story was featured on John Walsh's television show "The Hunt."

In October, People Magazine ran a feature about the Greenman Elementary School first-grader's disappearance.

Most recently, "20/20" on the Investigation Discovery Channel picked up the case, and will run its own program Dec. 28.

"We're hoping that the national exposure to Timmothy's case on a program as popular as '20/20' will result in information that will ultimately lead to finding him," Aurora Police Department spokesman Dan Ferrelli said.

Pitzen's case is one that has concerned investigators for years, he said.

On May 11, 2011, Timmothy was picked up from school by his mother, Amy Fry-Pitzen. It was 8:35 a.m., and Fry-Pitzen told school officials that there had been a family emergency. She had to take the boy and leave. But, there was no emergency, police said.

Instead, Fry-Pitzen took the boy on a whirlwind vacation. He spent the days leading up to his disappearance at the Brookfield Zoo, a water park in Gurnee, and finally, to a Wisconsin Dells resort where the last known sighting of Timmothy was caught on video.

National Center for Missing and / HANDOUT

Timmothy Pitzen is shown in age-progressed image to 10 years old. He has been missing from Aurora since May 12, 2011 and was last seen at a water park in Wisconsin Dells, Wisconsin., with his mother who was found dead in a motel in Rockford.

Timmothy Pitzen is shown in age-progressed image to 10 years old. He has been missing from Aurora since May 12, 2011 and was last seen at a water park in Wisconsin Dells, Wisconsin., with his mother who was found dead in a motel in Rockford. (National Center for Missing and / HANDOUT)

On May 13, at 11:15 a.m., the mother and son were seen checking out of the Kalahari Resort there. Two days later, Fry-Pitzen was found dead in a Rockford hotel, and Timmothy was gone.

A note was left behind: Timmothy was safe, with someone who loved him — and he would never be found, Fry-Pitzen wrote.

"His family has been through almost five years of heartbreak and every member of the Aurora police has been through almost five years of incredible frustration as we continue to hit brick walls in our efforts," Ferrelli said.

Throughout the years, there have been new clues, such as a cell phone that was discovered and trace evidence found on the wheels of Fry-Pitzen's car. Age progression photos have been released, and tips have filtered in throughout the country regarding possible sightings of the missing boy.

"Previous publicity of the case in the national media has resulted in some phone calls," Ferrelli said.

Following John Walsh's feature of the case, "The Hunt" received 20 tips, although a quarter of them were unrelated, according to investigators.

"Although they did not lead to Timmothy's whereabouts, the calls do demonstrate that people are taking note of his disappearance and are doing exactly what we need--- reaching out when they believe they have seen a child resembling him," Ferrelli said.

The case will be spotlighted at 8 p.m. Dec. 28 on the program "20/20 on I.D." and it is produced by ABC News. Investigations Discovery can be found on channel 271 on Comcast and channel 260 (1260 for HD) on AT&T U-Verse in Aurora. Consult local listings in other communities.

Anyone with information about Timmothy Pitzen's disappearance is asked to call Aurora police investigators at 630-256-5500.

A version of this article appeared in print on December 25, 2015, in the News section of the Chicago Tribune with the headline "Episode to explore case of Pitzen - `20/20' to focus on missing Aurora boy in Monday airing" —
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